From the tropics to the Arctic… I spent last week in Tromsø , Norway helping prepare the German icebreaker Polarstern for the MOSAiC year-long polar drift expedition. As I’ve written in past posts, I’ve been waiting for this moment since 2012 and it’s hard to believe it’s finally here. MOSAiC is a true coupled ocean-ice-atmosphere study, and the first such study of its scope or scale. There have been modern overwintering expeditions in the Arctic before – most notably the SHEBA expedition of the late 1990’s – but none have approached the breadth or scale of MOSAiC.
The basic idea behind MOSAiC is to drive Polarstern into the Laptev Sea and tether the ship to an (increasingly rare) large floe of multiyear sea ice. As we move toward winter, the floe and Polarstern will become encased in newly forming sea ice. The ship will drift with this ice through the full cycle of seasons, allowing a rare opportunity to study the physical, chemical, and biological characteristics of sea ice through its full progression of growth and decay.
But MOSAiC is about more than sea ice. Sea ice is – for now – a dominant ecological feature of the central Arctic, and it exerts a strong influence on both the atmosphere and the upper ocean. Better predicting the consequences of reduced sea ice cover on these environments is a major goal of the expedition.
With support from the National Science Foundation, for our own little piece of MOSAiC PhD student Emelia Chamberlain and I are collaborating with Brice Loose and postdoctoral researcher Alessandra D’Angelo at the University of Rhode Island, along with colleagues from the Alfred Wegener Institute in Germany. We’ll be looking at how the structure of prokaryotic and eukaryotic communities in sea ice and the upper ocean influence the oxidation of methane (a potent greenhouse gas), and the production and uptake of CO2. I’m looking forward to joining Polarstern in late January for a long, cold stint at the end of the polar night!
